Novice help with sub folder within 'main'

Hello,

I'm using uDemy to learn Git/Github, it's great. I've a little confused on some areas, but I'll get there with practise. I'm going round in circles on this part.

I have a local folder I've initiated with:

git init -b main

the folder local looks like this:

/opt/docker$ ls
config  config.env  docker-compose.yml

I simple want to push it to my github into a sub folder called 'main/projectx'

At the moment it uploads to the root of main. The good thing it's all working with commit, push etc. I'm not sure if this a branch, but how can I get it to push to 'main/projectx'? projectx doesn't exist in my github main repo, I assumed locally I could push it to there and it would create it.

Any help would be great.

Thanks